Centrifugal casting machine



' Juiy 11, 1933.- D. J. CAMPBELL 1,917,872

CENTRIFUGAL CASTING MACHINE Filed Nov. 9, 1951 3 Sheets-Sheet I I l IIll: 9 L 7 Yb 55 ACW Qmme g Donakl' c5. Cgmpbe \nuenToY Jufiy 1 1, 1933.

D. J. CAMPBELL E HZWZ CENTRIFUGAL CASTING MACHINE Filed Nov. 9, 1931 sSheets-Sheet 2 Donaud c). Cam mL Tiome 5 muen Im' y 1933- D. J. CAMPBELLCENTRIFUGAL CASTING MACHINE 5 Sheets$heet 5 Filed Nov. 9, 1931 operationPatented July 11, 1933 UNITED STATES PATENT OFFICE DONALD J'. CAMPBELL,OF MUSKEGON, MICHIGAN, ASSIGNOR TO CAMPBELL, & CANNON FOUNDRY COMPANY,OF MUSKEGON, MICHIGAN, A CORPORATION OF MICHIGAN CENTBIFUGAL CASTINGApplication filed November 9, 1931. Serial No. 573,949.

This invention relates to a centrifugal casting machine, the purpose ofwhich is to deposit molten metal at the inner side of a revolving drumand integrally fuse the molten metal with the material of the drum asdisclosed in my pending application, Ser. No. 512,792, relatin to aProcess of centrifugal castings, filed lfebruary 2nd, 1931, and toproduce specifically a double width drum having an outer shell of rolledor pressed metal and an inner integrallyfused band of cast iron which,after the process has been completed, may be divided between its edgesto make two flanges for automobile brake drums as shown in my' pendingapplication Ser. No. 544,350 for Composite drum, filed June 15th, 1931.

'The present invention is directed to an apparatus or machine foreffectively carrying out the process mentioned and for producing thedevices illustrated and described in the last mentioned application. Theinvention while of greatest use in connection with brake drums is not inany sense limited to such devices alone.

It is an object and purpose of the present invention to provide apractical machine and apparatus for casting and fusing cast metal bandsat the inner side of surrounding rolled or pressed metal drums, whereinspeed of in inserting the rolled or pressed drums and in ejecting thecomposite pressed drum with cast metal bands fused at theinner sidethereof is attained.

It is a further object and purpose of the invention to provide themachine with a simple and effective mechanism for depositing or pouringthe cast metal against the inner side of the outer rolled or pressedmetal drum in a measured amount so as to provide the necessary thicknessand yet not give too great a thickness of cast metal.

Other objects and purposes are to provide practical and'efiective meansfor the ready and easy insertion of the outer drum in a fixture and theclamping of the same against undesired movement while cast metaldepositing takes place and to free the composite drum after it has beenproduced; and to provide various other practical and novel features ofconstruction for effectively attaining the ends stated.

An understanding of the invention may be had from the followingdescription taken in connection with the accompanying drawings, inwhich, I

Fig. 1 is a front elevation of a machine for lining pressed metal drumswith inner" cast metal bands and fusing the same thereto.

2 is an end elevation thereof.

Fig. \3'is a fra entary plan View of one end of the mac ladle, turned toits outer filling position.

Fig. 4 is an enlarged central longitudinal sialction through the upperpart of thema- 0 me.

- sheet metal drum into which the molten metal is poured andillustrating to pour the molten metal.

Fig. 6 is a vertical longitudinal section through the composite drumproduced on'the machine.

Fig. 7 is a perspective view of the molten metal holding and pouringladle. Fig. 8 is a fragmentary enlarged view lllustrating the manner inwhich the composite drum, after it has been produced, is released fromthe machine,and'

9 is a fragmentary plan and partial section showing one method by meansof whlch the rotating fixture engaging head may be heated, if necessary.

Like reference characters refer to like parts in the different figuresof the drawings.

In the construction shown, a support 1- is provided above and resting onwhich is a head 2 having two spaced apart upwardly extending housings 3in which roller bearings 4 are mounted for the rotatable mounting of theladle tipped ine showing the pouring a hollow shaft 5 which lies betweenand ex- The shaft 5 is adapted to be rotated at a relatively high speed,which speed in operation will range from 900 to 1800 R. P. M., dependingupon the size and diameter of the drum being. processed. That is, a drumof large diameter will require slower rotation of the shaft 5 than willa smaller drum, and again, other factors such as the heat of the moltenmetal may enter in. For these and other reasons a rather wide range ofspeeds 1S necessary, the determination of which in each case lieslargely with the skilled operator in charge of the machine. A gear 9 onthe shaft 5 may be driven by an endless chain 10, which in turn passesaround a drive gear 11 on the shaft of a variable speed electric motor12 which is located conveniently andbetwecn the sides or lower part ofbase as shown in Fig. 1.

lVithin the hollow shaft 5 and extending the full length thereof andbeyond the same at its ends is a tubular shaft 13. It is threaded at itsouter end for the connection of a head 14 which is-located adjacent theinner end of the open head 6 previously described. At'the other end ofthe tubular shaft 13 is a ball bearing housing 15 carrying bearings 16whereby the shaft 13 may freely rotate within the housing 15. Sinceconsiderable heat is generated during the operation of the device hereinit may be desirable and even necessary in some instances to providemeans for water or otherwise cooling the bearings thereof, said meansnotbeing shown in the drawings however as such is not an essential partof the instant invention.

A rod 17, connected at one end to the housing 15, extends therefrom inaxial alincment with the tubular shaft 13 and carries a piston 18mounted within a c linder 19. The cylinder 19 is cast integral with andextends from one end of a housing 20 which in turn is connected to thesupporting head 2 of the machine, the housing 15-and parts of the shaft13 and rod 17 extending lengthwise centrally of the housing 20 e Thecylinder 19 is closed at both ends and has ports ateach end thereofthrough which compressed air or fluid may be entered or exhausted, usingpipes 21 which connect at one end to the cylinder ports and at the otherend to a valve housing 22 into which compressed air from a reservoirtherefor is carried by an inlet pipe 23. A valve 24 manu-- ally operatedby a handle 2 10, may be swung to two different positions to direct thecompressed air to either end of the cylinder 19 and open the other endof the cylinder to the outside through an exhaust port 25' (see Fig. 8).

It is apparent from the foregoing construcpiston 18 may be selectlvelymoved either to the forward position shown in Fig. 8 or to its backposition shown in Fig. 4; and the tubular shaft 13, with the head 14 atits forward end, is moved from outer to inner position or vice versadepending upon the position to which the piston 18 is moved. In Fig. 8the head 14 is shown at its outer position and in Fig. 4 at itsinnermost position. A rod 26 extends into the forward end of the tubularshaft 13 and for the major portion of its length, and bears against acoiled compressed spring 27 housed within the tubular shaft 13 andlocated between the end of the shaft 26 and a screw plug which closesthe inner end of the tubular shaft. (Fig. 8). The front end of the rod26 has a disk-like head 28 secured thereto with an annular groove 29 atthe curved edges of the disk.

A separable and contractible drum holder xture is connected withtheheads 14 and 28. The drum holding fixture is made up of a pluralityof segments each having an inner are shaped side 30 with spaced grooves31 therein, an outer tapering side 32, a front end 33 integrallyconnecting the front edges of the sides 30 and 32 and a rear end 34connecting the same at their rear edges; and from the rear end of eachof the segments a substantially trapezoidal shaped wing-35 extendsradially inward and is formed at its inner end with a rounded head 36 toenter the annular groove 29 in the head 28 (Fig. 8). The space 37enclosed by the sides 30 and 32 and ends 33 and 34 in each segmentsuitable heat insulating substance. In either case the dissipation ofheat outward is very materially checkedso that when the pressed 37 maybe cooled by air passing therethrough or by other suitable means.

From the segments thus described fingers are forced to closed position,as shown in Fig. 4, through the bearing of the tapered inner sides ofthe flange 7 against the tapered outer sides 32 of the foregoing it isapparent that this composlte member becomes, when closed, a true saidsegments. From of flange die to hold an article such as abrake drum, theshape and size of said die being determined b ments thereof. This formmust be large enough to take care of the expansion of the heated theformation of the completed drum, as is explained more in detailelsewhere in this specification. From .008 to .012 per inch of diameteris usually allowed in the form for expansion, and for this reason a colddrum placed in the die has such clearance that it will hardly formsufiicient contact therewith to rotate. The allowance in the die forexpansion of the drum must depend largely upon the temperature to whichthe drum is heated befoiaadnsertion forcasting, the higher thetemperature the greater the expanslon.

A drum 41 of pressed or r\olled metal may be formed with spaced annularbeads 42 and at the ends with inwardly turned annular lips 43. Thesedrums are heated to a temperature of somewhere within the range of 1200to 1500 Fahr. With the holding fixture in outer position, as in Fig. 8,the drum is inserted into the fixture and then by turning the handle 24ato, the position shown in Fig. 4 drawn into the head 6 and the fixtureclamped against the drum, the beads 42 seating in the annular grooves"31 of the fixture segments. Although the segments of the inner formherein have been described as having annular grooves 31, it is apparentthat the presence or absence of such grooves may depend largely upon theparticular type and shape of drum being processed at the time, and forwhich the die has been prepared. A drum with a fiat outer surface willrequire no grooves in the form, and in fact, such would be useless,while a drum with one or more beads (Fig. 6) or other surfaceirregularities will work best with a die formed with correspondingindentations, the purpose in each case being to iiisure efiicientengagement between the drum and the .form.

It is likewise apparent that with the apparatus in drum receivingposition, as in Fig. 8, there is no positive driving connection causingthe shaft 13, head 14 and the fixture segments to rotate, but that assoon as the piston 8 is forced tothe outer end of cyhnder 19, as in Fig.4, the fixture, being in firm frictional engagement with the inner sides7 of head 6 and in further engagement at the back ofthe spider head 14as at 14a, will rotate with said head 6. Likewise it is evident that onthe contraction of the fixture against the the attached rod 26 are movedinwardly with a compression of the spring 27 which also acts to forcethe outer sides of the segments of the fixture into firm contactengagement the contact joints between the seg-' drum, which expansion 1sa factor in the fixture with the drum therein will be drum 41, head 28andwith the inner sides of the flange 7, whereby rotation of the drumwill be insured.

A supporting bracket 44 (Fig. 1) extends from one end of the support 1,carries the hood 8, and is utilized for mounting the ladle carrying arm45 which at one end is formed 51 to the upturned end 45a of the arm 45.In

order to protect the outer shell thereof from burning through whenfilled with molten metal, the interior of the ladle 49 is lined withfireclay or other suitable refractory material.

The arm 45 has a branch 52 (Fig. 2) extending downwardly to which avertical air cylinder 53 is pivotally connected. A piston rod 54,operated by the action of compressed air entering the lower end of thecylinder 53, extends from the upper end of the cylinder and is pivotallyconnected to other ears depending from the lower side ofthe ladle 49;whereby on upward movement of the rod 54 the ladle is tippedv from itshorizontal position, shown in Fig. 2, to the pouring position shown inFig. 5. Although the actuation of the piston 54, and more particularlythe tilting of the ladle 49 in connection therewith, has been describedas being accomplished by means of compressed air herein, it is apparentthat this action may be effected in a number of different ways, as, forinstance, by manually tilting the ladle, orby using fluid pressure meansto do this, or for that matter by employing any suitable force to securethe desired result. The ladle at its upper edges on opposite sides isformed with depressions or notched recesses 55 and 56 (Fig. 7). Thenotch 55 governs the level of molten metal in the ladle when it is inits filled position as shown in Figs. 2 and 3, while the longer recessesat 56 governs the width of the stream of molten metal which flows fromthe ladle when it is tipped to pouring position.

Compressed air carried in a pipe 57 to and through a valve housing 58and thence through a tube 59 may be entered into the lower portion ofthe cylinder 53 to elevate the rod 54 and tip the ladle, a valve in thevalve housing 58 being utilized for control- *ling the How of air so asto tip the ladle gradually and cause the pouring to be uniform from thetime the same begins until the ladle is completely tipped and all of themolten cast metal therein has been poured.

It is designed that the head 6 shall itself be initially heated and, ifnecessary, kept at the des red range of temperature by heat or, coldapplied thereto as may be required. In

Fig. 9 is shown one way in WllICh said head may be heated, that is, byan electrical heating element 60 partly around the same. Similarly, acooling unit may be utilized. In practice, at the beginning of theoperation of the machine, the head may also be initially heated by ablow torch and thereafter reliance placed upon the escape of heat fromtheheated drums 41 and from the molten metal which is poured into saiddrums to maintain the head 6- at a desired working temperature. In thissituation the radiation of heat through the space 37 is regulated asdesired by utilizing a heat conducting material of the desiredcharacteristics therein.

The shaft, 5 as shown in Fig. 4, may also be equipped with any suitablebrake to stop its rotation and at 61 there is indicated a magnetic brakefor such purpose.

lVith the drum holding fixture in its outer expanded position, as inFig. 8, a drum 41, heated .to a temperature within the range of 1200 and1500 Fahr. approximately, is placed within the open expanded segments ofthe fixture and the handle 24a turned from the position shown in Fig. 8to that shown in Fig.4, whereupon the fixture with the drum in it aredrawn to inner position as shown .in Fig, 4. In the meantime or at thesame time the ladle 49 is filled with the molten cast iron. While suchfilling of the ladle is taking place the arm 45 on which the ladle iscarried is swung to outer position shown in Fig.3. The molten cast iron,indicated at 62, fills the ladle until it overflows at the overflownotch. Arm 45 and the ladle are then swung through an arc ofsubstantially 90 so as to bring the ladle partly within the drum carriedby the contracting fixture described. The valve 58 is opened so as topermit the passage of a predetermined con-' tinuous quantity ofcompressed air to cylinder 53 whereupon the ladle is progressivelytipped and molten iron flows in a thin sheet, indicated at 63, over theoutlet lip at the bottom of the recess 56 and deposits upon the rapidlyturning drum 41, which drum is rotated at a suitable speed as explainedpreviously herein. In practice it takes anywhere from three to tenseconds to empty the ladle and during this time the drum will haveturned through many revolutions. If, for example, the molten cast ironis deposited in three seconds the drum at 1100 R. P. M. will have turnedthrough fifty-five revolutions; and if five seconds are consumed thedrum will have turned through more than ninety revolutions.

After the iron from the ladle has been poured the valve at 58 is turnedto exhaust the compressed air whereupon the ladle'will return to itsnormal position; and the ladle and arm 45 are swung outwardly to theposition in Fig. 3/ After a reasonable time for the molten cast iron tosolidify, handle 24a is turned to the position shown in Fig.8 whereuponthe drum and fixture are moved outwardly and as the outer sides of thesegments of the fixture leave the contracting flange 7 around them theyare automatically expanded through the force of the compressed spring27, and the composite drum 41 lined with a cast metal lining 64integrally fused thereto is removed from the fixture and the apparatusis in condition for a repeating of the process.

The construction described is one very practical and useful and hasproved exceptionally practical in quantity production of composite drumstructures of the character described. The range of the temperature forthe molten iron should be between 2600 and 3000 F ahrI. In practice forthe best results and to secure a complete fusing at the contactingsurfaces of the molten cast iron and the outer pressed drum thetemperature of the drum should not be much below 1350 Fahr, thoughsatisfactory production in most cases can be obtained with the outsidedrum at 1200 of more Fahr. with the temperature of the molten cast ironhigher than the minimum of 2600 F ahr. which has been stated. Theinvention is defined in the appended claims and is to be consideredcomprehensive of all forms of structure coming within their scope.

I claim:

1. In a machine of the class described, a rotatably mounted shaft, meansfor driving the same, a head open at one end and having tapered innersides at one end of the shaft, a tubular shaft mounted lengthwise of thefirst shaft, a second head mounted at one end thereof and located withinthe first head, a rod located lengthwise of the tubular shaft,a'threaded head secured at one end of the rod ad acent the second headand within the first named head, a fixture adapted clamp against asubstantially cylindrical drum of rolled or pressed metal comprising, aplurality of segments connected with the two last mentioned heads, meansfor selectively moving the tubular shaft longitudinally in eitherdirection to draw said fixture into the first head and close thesegments thereof against the drum, and yielding means for causing saidsegments to separate on longitudinalmovement of the tubular shaftoutward to carry the fixture segments out of the first mentioned head.

A construction of the class described, comprising, a horizontalrotatably mounted shaft, an enlarged head having an open outer verticalside at one end of the able therewith, means for driving the shaft,

pushed partially out of said head, said segto receive and ments havinginwardly extending wings at their inner ends, a rod located lengthwiseof and within the tubular shaft, means for pivotally connecting theinner ends of said wings to an end of said rod, means for connectingeach of said segments to an end of said tubular shaft, spring meanshoused within the tubular shaft acting on said rod tending to force-thesame outwardly, and means-for selectively moving said tubularshaftlongitudinally .in either direction. A

3. In a construction of the class described, a rotatably mounted headhavingan open side the inner sides ofi said head being tapered inwardly,a drum holding fixture comprised of a series of segments located aroundthe axis of said head, means for rotating the head,

'means for simultaneouslydrawing all of the DONALD J. CAMPBELL.

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